信息安全，密码学，rail fence cipher加密明文，秘钥长度4，顺序为4213

Question

信息安全，密码学Cryptography，rail fence cipher加密明文”welcome to computer science,秘钥长度4顺序4213

Answer 1

import re


def Encipher(plaintext, keyLength, order):
    result_str = ''
    plaintext = plaintext.replace(" ", "")
    text_list = re.findall(r'.{%s}' % keyLength, plaintext)
    index = [i for i in range(keyLength)]
    index = sorted(index, key=lambda item: order[item])
    for i in range(keyLength):
        for text in text_list:
            result_str += text[index[i]]
    return result_str


if __name__ == '__main__':
    plaintext = input('plase input plaintext: ')
    keyLength = int(input('plase input keyLength: '))
    order = input('plase input order: ')
    ciphertext = Encipher(plaintext, keyLength, order)
    print('ciphertext =', ciphertext)